Many medical devices use optical fibers to transmit laser energy from a laser source and/or light from a light source. After each use, the efficiency of the optical fiber decreases and energy provided to the proximal end of the optical fiber may not result in as much energy transmitted to the distal end as previous uses. As a result, operators often replace an optical fiber after a certain number of uses (e.g., ten uses) or certain amount working time (e.g., fifteen hours of working time). In some cases, the optical fiber is still sufficient for additional uses or use time, but the operator does not know whether or how many additional uses are still available. Replacing and discarding an optical fiber when it still has the ability to provide additional uses results in an additional costs to users and increased waste. As such, there exists a need for a testing device to test the efficiency of optical fibers and thus, reduce the cost and waste associated with optical fibers in medical devices.